Compressor



Oct. 19,1926. 1,603,983 w. G. E. ROLAFF COMPRESSOR Filed ust 7. "1925 sSheets-Sh-et 1 INVENTOR Wm. 1-52? 6. 5. Fob/1H;

ATTORNEY Oct- 19 1926. 1,603,983

- w. G. E. ROLAFF COMPRESSOR I Filed August '7, 1925 3 Sheets-Sheet 2INVENTOR A/Au'me 6. 6. ZOLAFF.

A TTORNE Y W. G. E. ROLAFF Oct. 19 1926.

COMPRESSOR Filed August '7. 1925 3 Sheets-Sheet 5 l' INVENTOR WAL. To?6. PoL/1FF A TTORNE Y Patented Oct. 19, 1926.-

UNITED STATES warren e. E. Blomrr, or am LOUIS, urssounr.

cournnsson.

Application filed August 7, 1925. Serial No. 48,725.

This invention relates to improvements in rotary compressors, designedmore particularly for use in the art of mechanical refrigeration, but,in principle, equally applicable for use in the general art ofdisplacing liquids and gases.

Certain broad principles of the invention are described and claimed inmy prior applications Serial Nos. 33,951 and 33,952, filed June 1st,1925, the first showing the embodiment of the invention in a rotary pumin which the rotor engages directly with the end walls of the cylinder,and the second showing the invention embodied in a rotary "compressor inwhich the rotor is provided with a unitary head, preferably formedintegral therewith, the end of the rotor and the inner wall of the headengaging opposite ends of the cylinder, respectively, to

form sealing contact therewith.

The object of the present invention is to provide a floating head inplace of the unitary head shown in my application Serial No. 33,952,above referred to, and to provide means for actuating this floating headat a definite speed from the shaft which actuates the rotor. .In thepreferred'embodiment of the invention, as shown in the drawings, this isaccomplished by an eccentric mounted on the shaft, on which the rotatinghead has a sliding fit. The invention contemplates the use of twofloating heads instead of a single floating head at oneend ofthe rotor,and it is within the scope of the, invention to givethe floating head,or the floating heads if two be employed, a sliding fit on the shaft ofthe rotor, and to hold the head or the heads to the end or ends of thecylinder by developed pressure, Without employing an eccentricconnection between the shaft and the floating head or heads.

, of two floating heads; and

Figure 3 is a view partly in cross-section and partly in elevation ofeither of the machines shown in Figures 1 or 2.

Referring now to the drawings, the numeral 1 (Figure 1) indicates acasinglcom prising end sections 2 and 3 bolted to a central annularsection 4, the inner surface 5 of which constitutes the working surfaceof a cylinder. having a working chamber 6. The inner face 7 of the endsection 2 of the casing forms one wall of'this c linder, and the otherwall is formed by a oating head 8 which bears against and forms sealingcontact with one end of a hollow rotor 9, the other end of which bearsagainst the flat face 7 of the end section 2 to form a sealing contacttherewith for the chamber 6. The inner side of the head 8, beyond therotor 9, bears against an annular flange 10 on the annular section 4 toform a sealing contact atthis end of the cylinder for the chamber 6.Each of the sections 2 and 3 is recessed, as indicated at 11 and 12,respectively, to provide space for anti-friction bearings 13 and 14, inwhich bearings is mounted a drive shaft 15. This drive shaft, in thepreferred embodiment of the invention, is provided with an eccentric 16on which the sliding :head 8 is centrally and rotatably mounted.

As the shaft rotates, the eccentric 16 imparts an eccentric movement tothe head 8,

so that the latter is actuated at a definite speed, and i ts inner faceis caused to continuously wipe over the face of the annular flange 10,which insures a smooth clean bearing between the two surfaces topreservethe air-tight contact between them in the operation of thecompressor. between the floating head, the flange 10 and one end of therotor 9 (that at the right shown in Figure 1), and between the other endof the rotor and the wall 7 of the cylinder, is'ma-intained by developedpressure in the operation of the machine. The annular rotor 9 is mountedon the. shaft 15 in such manner as to' provide for, automaticallyproducing and maintaining a sealing contact with the wall 5 of thecylinder, and also to be self-alining therewith.

Sealing contact To this end, I provide on the shaft 15 a I secondeccentric 17 which-is circular in cross section, and mount on thiseccentric an eccentric sleeve 18.. That is to sayfthe sleeve 18 has aneccentric bore which flts. on the eccentric 17 so as to be capable ofrotating thereon, the construction providing a double eccentric, whichfunctions automatically as a take-up for the space between the rotor andthe cylinder- Mounted on the eccentric "sleeve 18 to extend between thesame and the inner wall-of rotor 9 is asingle self-'alining Y bearing 19which supports the rotor, This bearing in combination with the eccentrlcsleeve 18, allows universal alinement of the rotor to the cylinder wall,both as to par- I allelism and plane. The stuffing box for the with ashaft opening 23 of larger diameter inafter appear;

than the shaft, through which-the medium being compressed can pass intothe bellows 20, which will, accordingly expand and force its other end,which is in the form of a packing ring 24, firmly against the outer sideof the wall 22 to make sealing contact therewith and prevent the escapeof the compressed medium. The bellows 20 is located in a chamber 25 castin the casing section 3, which chamber is closed by a plate 26, operatedto permit the driving end of the shaft to pass through it.

In the modification shown in Figure 2, instead of having one end of therotor engage the wall'of the cylinder, as just described, I employ asecond floating head, indicated at 27, which ismou'nted upon aneccentric 28 in the same manner as the head 8 is mounted on theeccentric 16. The end section of the cylinder corresponding to the endsection 2 of Figure 1, is indicated by the numeral 29 and, as shown, 1sprovided withan annular space or chamber 30 for containmgdubricant underpressure, as W111 here- Referring now to Figure 3, the numeral 31indicates an inlet or suction port, through which the mediunr to becompressed may pass or be sucked'in in the operation of the compressor.To this port is connected a. pipe 31 leading from the low side orexpansion chamber of the refrigerating system; and

through which the refrigerant is returned for compression, as will beunderstood. The

numeral 32 indicates an outlet from the cylinder, which is provided Withany suitable form of chuck valve 33. The ports 31 and 32 are preferablyprovided .in a casting formed integral with the cylinder,.andintermediate these ports, a portion 34 of this casting is provided witha slot 35, which is of the length of the cylinder 6, and in this slot islocated a blade 36 which is preferably of the self-packing type of myprior Patent No. 1,280,306, dated October 1st, 1918/ This plicationSerial No. 33,951, above'referred to; but I prefer to use a fluid,-and,specifically, utilize the lubricant employed in the system for thispurpose.

To this end, the outer end of the slot 35 terminates in a small chamber42 with which communicates one end of a pipe 43, which is screwed intothe annular section 4, the other end of said pipe being screwed intoth'ewall of the casing section 3 near the bottom thereof to communicatewith. an annular chamber 46, vwhich surrounds a centralinwardly-projecting cylindrical casting 45, in which is housed thebearing 14 and bellows 20, previously described; This casing'is anintegral part of the casingsection 3. Ac;- cording to this construction,when the rotor is placed in operation, the medium being compressedpasses through the pipe 43 into the chamber 42 and forces the inner edgeof the blade 37 into sealing contact with the surface of the rotor, and,of course, maintains such contact. s

In order to facilitate the direct pressure of the fluid upon the centralWedge-plate 41, an opening 44 may beprovided in theshoulder 38 to permitaccess of the fluid to the wedge-plate, which,vaccordingly, operates toforce the, packing plates 39 and 40 into engagement with the end'wallsof the cylinder to form sealing contact therewith, which contact isautomatically maintained during the operation of the compressor.

The bearing 14 and the bellows 20 are housed within the casting 45. Thechambers 30 and 46 are supplied with a suitable lubricant, such as oilor glycerine, the level of which in the chambers is maintained at aboutthe height indicated by the dotted line 47. Mounted on top of the casingsection 3 is an oil-separating chamber 48, which communicates with thechamber 46 by meansof a pipe 49. Leading from the upper end of thischamber is a pipe 50 which, when the compressor is combined with arefrigerating system, conducts the compressed gaseous refrigerant fromthe chamber 48 to the ordinary condenser. Connected with the outlet port32 is a pipe 51 (Figure 3) which conducts the compressed gas andoil fromthe compressor to,the o l-separatingcbamber 48. In this chamber. the oilseparates from the refrigerant and flows back into the chamber 46, whilethe gaseous refrigerant passes out through pipe 50 to the condenser, asstated. From the condenser,

the refrigerant would pass to the expansioncoils or chamber of arefrigerating system and thence be drawn back into the compressorthrough the pipe 31.

moaese In the operation of the device, as the shaft rotates, thecombined operation ofv the wall of the cylinder chamber 6. In thisoperation, the medium to be compressed, which in connection with the artof refrigeration, would be a suitable gas, such as methyl chloride, willbe drawn in through port 31', compressed in the chamber 6,.and forcedout through port 32. A certain amount of lubricant in the chamber46 willpass out with the gas, and gas and lubricant will be forced through pipe51 into chamber 48 in the mannerpreviously stated,

The lubricant in the chamber 46 will be under pressure, as chamber 46communicates with chamber 48 into which the compressed gas is delivered,which causes the lubricant to be forced through pipe 43 into the smallchamber above the blade 37, upon which it exerts its pressure, andforces the lower edge of the blade into sealing contact with the surfaceof the rotor O. Ordinarily, the oil can leak past the shoulder 38 toexert its pressure upon the wedge-plate 41, but the provision of thesmall aperture 44 in the shoulder will be found desirable in theinterest of permitting the pressure of the oil to be exerted directlyupon the wedge-plate. In either event, the packing plates 34- and 35will be forced into sealing contact with the end wall 7 of the cylinderand with the inner face of the floating head 8 of Figure 1 or with theinner faces of the floating heads 8 and 27 of Figure 2.

As in the case of the device of my prior application Serial No. 33,952,suitable springs 52 may be located in the chamber 46 to exert pressureupon the floating head 8, so that the operation of compression may startsimultaneously'with the re tation of the shaft 15. Similar springs 53may be employed in the chambers 30 and 46 of the device of Figure 2 toact on the floating heads 8 and 27 for the same purpose. It

is not absolutely essential, however, that any means should be employedfor forcing these floating heads into sealing contact with the wall ofthe cylinder, as, after a few moments of operation, sufficient pressurewill be developed on the oil in the chamber 46, or in the chambers 30and 46, to

cause the latter to 'force the heads into sealing contact with thecylinder.

The action of the double eccentric, com-' prising the shaft eccentric 17and eccentric sleeve 18, has been fully set forth in my priorapplication'Serial No. 33,951, referredv to, and it need only be saidhere, in the interest of a complete understanding of the invention, that7 these eccentrics operate through the medium of the self-aliningbearing 19 to force the'rotor outward into engagement with the wall ofthe chamber 6, and to maintain a constant automatic adjustment of therotor to compensate for wear. Furthermore, the contact pressure of therotor with the wall of the cylinder will be in direct proportion to theresistance offered to the movement of the rotor by the degree ofpressure within the chamber 6,

due to the resistance offered by the medium being compressed. This isdueto the fact that with increased resistance. to the movement of therotor, the latter is automatical- 1y forced into firmer contact with thewall of the cylinder by the action of the eccentrics. Sealing contact ofthe rotor with the wall of the cylinder is therefore always maintained.

A highly important feature of the invention is the fact'that, in thedevice of Figure 1, I employ a floating head 8 which is in dependent ofthe rotor, which may move away from the flange 10 of the cylinder topermit the escape of compressed gas from the chamber 6 under a conditionof excessive pressure in said chamber, .and which is positively actuatedby the eccentric 16 on the shaft to have imparted to it a correspondingeccentric movement, so ,that its inner surface and the surface of theflange 10 and of the ends of the rotor engaged by it will be maintainedbright and clean in thearea of contact, thus preventing any tendency toleakage. Furthermore, the wear caused by the frictional enga ement ofthe head with the ends of the cy inder and of the rotor will be uniformand over a defined area, so that no unevenness between the engagingsurfaces can well develop, and sealing contact between such surfaceswill be maintained under conditions of wear during the life of themachine. The ability of the floating head to move away from the flange10 to permit the escape of gas is, of course, due to the fact that it isnot fixed to the rotor or to the shaft, but is slidably 'ble to thefloating heads 8 and 27 f Figure 2.

I have 'shown no definite passage connecting the chamber 46 with thechamber 30 to permit the passage of oil from one to the other as, underthe very high pressure developed in the operationof the machine, the oilwould readily pass through the bearings from one chamber to the other.

The provision of a floating head,'or float- 1 ing heads, capable oflongitudinalmovement is of very great advantage, as it provides for therelease of pressure within the chamber 6 in the simplest possible way,avoids the use of check' valves and the like, and hence permits of theemployment of the minimum skilled in this art.

I'claimz.

1. A machine of the class described, comprising a cylinder, closed atone end, a rotor mounted for gyratory movement within the cylinder inco-operative relation with the wall thereof, a floating head releasablyengaging one end of said rotor and the other end of said cylinder toclose the latter, and means for holding said head in fluid-tight contactwith the end of the rotor and said other end of the cylinder.

2. A machine of the class described, comprising a cylinder closed at oneend, a rotor mounted for gyratory movement within the cylinder inco-operative relation with the wall thereof, a floating head releasablyengaging one end of said rotor and the other end of said cylinder toclose the latter, means for continuously moving said head in theoperation of the compressor, and means for holding said head influid-tight contact with the end of the rotor and said other end of thecylinder.

3. A machine of the class described, comprising a cylinder closed at oneend, a rotor mounted for gyratory movement within the cylinder inco-operative relation with the wall thereof, a floating head releasablyengaging one end of said rotor and the other end of said cylinder toclose the latter, means for continuously imparting a gyra-tory movementto said head in the operation of the compressor, and means for holdingsaid head in fluid-tight contact with the end of the rotor and saidother end of the cylinder.

4. A machine of the classdescribed, comprising a cylinder closed at oneend, a rotor mounted for gyratory movement within the cylinder inco-operative relation with the wall thereof, a rotary shaft foractuating said rotor, an eccentric on said shaft, a floating headslidably mounted on said eccentric and engaging one end of said rotorand the other end of said cylinder to close a the latter, and means. forholding'said head in fluid-tight contact with the end of the rotor andsaid other end of the.cyl1nder.

5. A machine of the class described, com

prisinga stationary cylinder closed-at one end, a rotor mounted forgyratory movement with the wall thereof, a floating head re-' leasablyengaging oneend of said rotor and .the other end of said cylinder toclose the latter, and means for holding said head in.

fluid-tight contact with the end of the rotor and said other end of thecylinder.

6. A machine of the class described, comprising a cylinder closed at oneend, a rotor mounted for gyratory movement within the cylinder inco-operative relation with the wall thereof, and a floating headreleasably engaging one end of said rotor and the other end of saidcylinder to close the latter and adapted to be held in fluid-tightcontact with the end of the rotor and the said other end of the cylinderby the developed pressure of the compressor.

' 7. A machine of the class described, compris ng; a stationary cylinderclosed at one 5 end, a drive shaft mounted therein, an eccentric mountedon said shaft, a rotor rotatably mounted on said eccentric, a floatinghead releasably engaging one end of said rotor and the other end of saidcylinder to close the latter and slidably and eccentricallymounted onsaid drive shaft, and means for maintaining said floating head influid-tight contact with the end of the rotor and said other end of thecylinder.

8. A machine of the class described, coirpris'ing' a stationary cylinder.elosedat one end, a drive shaft mounted therein, a double compensatingeccentric mounted on said shaft, a rotor rotatably mounted on saiddouble eccentric in co-operative relation with the wall of saidcylinder, a floating head 'engaging one end of said rotor and the otherend of said cylinder to close the latter and slidably and eccent-ricallymounted on said shaft, and means for holding said head in fluid-tightcontact with the end of the rotor and said other end of the cylinder.

9. A machine of the class described, com-- prising a cylinder, a rotormounted for gyratory movement within the cylinder in cooperativerelation with the wall thereof, said rotor having an end releasablyengaging one Y end of the cylinder, a floating head releasably engagingthe other end' of said rotor and the other end of said cylinder to closethe latter. and means for holding said head in fluid-tight contact-withsaid other ends of'the rotor and cylinder.

10. A machine "of the class dgescribed, comprising a stationarycylinder, a drive shaft mounted therein, an eccentric mountedon saidshaft, a rotor ,slidably and rotatably mounted on said eccentric andhaving an end releasably engaging one end of said cylinder, a floatinghead releasabl engaging theother end of said rotor and t e other endof'said cylinder to close the latter, said head being subject topressure developed within the compressor, whereby it will be maintainedin fluid-tight contact with the ends of the rotor and cylinder which itengages, and said rotor will be maintained 1 at its other end influid-tight contact with themylinder.

11. A machine of the class described, comprising a stationary cylinder,a drive shaft mounted therein, an eccentric mounted on said shaft, arotor slidably and rotatably mountedon said eccentric and having an endreleasably engaging one end of said'cylinder, a floating head releasablyengaging the other end of said rotor and the other end of saidcylinderto close the latter and being slidably and e'ccentric'ally mounted onsaid shaft, said head being subject to pressure developed within thecompressor, whereby it will be maintained in fluid-tight contact withthe ends of the rotor and cylinder which it engages. and said rotor willbe maintained at its other end in fluid-tight contact with the cylinder.v

12. A- machine of the class described, comrisin a casin rovidin achamber for re- P r: H

ceiving a lubricant, acylinder mounted in said casing and having one ofits ends suitably closed, a rotor mounted for gyratory movement withinthe cylinder in co-operative relation with the wall thereof. a floatinghead releasably engaging the other end of said cylinder to close thesame and exposed to the lubricant within said chamber, and a separatingchamber adapted to receive the compressed medium audlubricant from thecylinder and communicating with the chamber of said casing, whereby saidfloating head will be maintained in contact with said other end of thecylinder by pressure developed within the machine.

13. A machine of the class described, comprising a casing providing achamber for receiving a lubricant, a stationary cylinder mounted in saidcasing and having one of its ends suitably closed, a rotor mounted forgy'ratory movement withid the cylinder in co-operative relation with thewall thereof, a floating head releasably enga ing one end of said rotorand the other en of said cylinder to close the latter and exposed to thelubricant within said chamber, and a separating chamber adapted toreceive the compressed medium and lubricant'from the cylinder andcommunicating with the chamber of said casing, whereby said floatinghead will be maintained in fluid-ti ht contact with the end of the rotorandsaid other end of the cylinder. I

In testimony whereof, I have hereunto set my hand.

WALTER e. E. ROLAFF.

